Attended collection and delivery points are vital components of ‘last-mile logistics’.Based on point of interest(POI) data for Cainiao Stations and China Post stations in Changsha City, China, this paper provides a ...Attended collection and delivery points are vital components of ‘last-mile logistics’.Based on point of interest(POI) data for Cainiao Stations and China Post stations in Changsha City, China, this paper provides a detailed exploration of the basic features, spatial distribution, and location influencing factors of attended collection and delivery points.Specifically, analyses of the types, service objects and location distributions of the attended collection and delivery points alongside a discussion of their spatial pattern and influencing factors provides a reference for their general geographic layout and characteristics.The findings of this study indicate that: 1) The main mode of operation of attended collection and delivery points is franchises, with other modes of operation rely on supermarkets and other individual shop types.2) The main service targets of attended collection and delivery points are communities, schools, and businesses, followed by townships, enterprises, scenic spots, and administrative units.3) Approximately 77.44% of the attended collection and delivery points are located near the exits of service areas;others are situated in the centre of the service areas.For the Cainiao Stations, 80% are located within 125 m of the exit;for the China Post stations, 80% are located within 175 m of the exit.4) The spatial distribution of the attended collection and delivery points in Changsha is unbalanced, with ‘more centre and fewer surrounding’.The centre is an ‘inverted triangle’, and the edge is an ‘orphan’, showing a northwest-southeast orientation and symmetrical along the axis.The layout of the attended collection and delivery points forms three core areas, and the number of sites decreases with the distance from the core.5) The number and distribution of the attended collection and delivery points are strongly consistent with the regional economic development level, population, and roadway system traffic convenience.Most attended collection and delivery points are on residential, scientific and educational, and commercial and financial land.展开更多
By applying the technique of continuous partition of unity and Tychonoff's fixed point theorem,. some new collectively fixed point theorems for a family of set-valued, mappings defined on the product space of nonc...By applying the technique of continuous partition of unity and Tychonoff's fixed point theorem,. some new collectively fixed point theorems for a family of set-valued, mappings defined on the product space of noncompact G-convex spaces are proved. As applications, some nonempty intersetion theorems of Ky Fan type for a family of subsets of the product space of G convex spaces are proved; An existence theorem of solutions for a system of nonlinear inequalities is given in G-convex spaces and some equilibrium existence of abstract economies are also obtained in G convex spaces. Our theorems theorems of improve, unify and generalized many important known results in recent literature.展开更多
Based on a KKM type theorem on FC-space, some new fixed point theorems for Fan-Browder type are established, and then some collectively fixed point theorems for a family of Ф-maps defined on product space of FC-space...Based on a KKM type theorem on FC-space, some new fixed point theorems for Fan-Browder type are established, and then some collectively fixed point theorems for a family of Ф-maps defined on product space of FC-spaces are given.These results generalize and improve many corresponding results.展开更多
This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 inn...This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 innovation design was proposed.Second,field-coupling theoretical models of sunlight concentration,photoelectric conversion,and transmitting antennas were established,and a systematic optimization design method was proposed.Third,a beam waveform optimization methodology considering both a high beam collection efficiency and a circular stepped beam shape was proposed.Fourth,a control strategy was developed to control the condenser pointing toward the sun while maintaining the transmitting antenna toward the rectenna.Fifth,a high-efficiency heat radiator design method based on bionics and topology optimization was proposed.Sixth,a method for improving the rectenna array’s reception,rectification,and direct current(DC)power synthesis efficiencies is presented.Seventh,high-precision measurement technology for high-accuracy beam-pointing control was developed.Eighth,a smart mechanical structure was designed and developed.Finally,the developed SSPS ground demonstration and verification system has the capacity for sun tracking,a high concentration ratio,photoelectric conversion,microwave conversion and emission,microwave reception,and rectification,and thus satisfactory results were obtained.展开更多
针对城市电网故障早期阶段的隐蔽性、潜伏性特点,通过构建“集体离群点-故障模式”的度量规则,对电网系统中全等级异常电流波动信号进行层次聚类分析,将区域性潜在故障检测问题转换为挖掘故障信号数据中的集体离群点问题。为提高检测效...针对城市电网故障早期阶段的隐蔽性、潜伏性特点,通过构建“集体离群点-故障模式”的度量规则,对电网系统中全等级异常电流波动信号进行层次聚类分析,将区域性潜在故障检测问题转换为挖掘故障信号数据中的集体离群点问题。为提高检测效率,设计了一种基于不动点迭代法的层次聚类改进算法(Fixed point iteration based k-medoids,FPK-medoids),利用不动点较强的局部搜索能力提高聚类收敛速度。在测试数据集和实例数据集上进行实验,结果表明改进算法的收敛性能优于传统算法,检测模型能够精准识别电网中的区域性潜在故障。展开更多
新能源汽车无人驾驶障碍检测过程中,受道路上的多种障碍物以及复杂的天气如雨雪、雾霾等影响,数据采集难度较大,导致驾驶障碍检测精度偏低。为此,提出车载激光雷达下新能源汽车无人驾驶障碍检测方法。采取水平安装的方式,将两个32线激...新能源汽车无人驾驶障碍检测过程中,受道路上的多种障碍物以及复杂的天气如雨雪、雾霾等影响,数据采集难度较大,导致驾驶障碍检测精度偏低。为此,提出车载激光雷达下新能源汽车无人驾驶障碍检测方法。采取水平安装的方式,将两个32线激光雷达以对称方式布置在无人驾驶汽车上,采集路面结构三维点云数据并用坐标转换同步数据;基于统计特征的离散点滤波算法,计算点云数据集的标准差和全局距离平均值,以此去除离散噪声点;采用基于密度的带有噪声的空间聚类(Density Based Spatial Clustering of Applications with Noise,DBSCAN)聚类算法实现新能源汽车无人驾驶的障碍检测。实验结果表明,所提方法抗噪能力较高,平均识别距离为82 m,障碍检测准确率均在92%以上,误检率最高为1.8%,且检测耗时仅为1.09 ms。展开更多
基金Under the auspices of the Tang Scholar Program of Northwest University(No.2016)
文摘Attended collection and delivery points are vital components of ‘last-mile logistics’.Based on point of interest(POI) data for Cainiao Stations and China Post stations in Changsha City, China, this paper provides a detailed exploration of the basic features, spatial distribution, and location influencing factors of attended collection and delivery points.Specifically, analyses of the types, service objects and location distributions of the attended collection and delivery points alongside a discussion of their spatial pattern and influencing factors provides a reference for their general geographic layout and characteristics.The findings of this study indicate that: 1) The main mode of operation of attended collection and delivery points is franchises, with other modes of operation rely on supermarkets and other individual shop types.2) The main service targets of attended collection and delivery points are communities, schools, and businesses, followed by townships, enterprises, scenic spots, and administrative units.3) Approximately 77.44% of the attended collection and delivery points are located near the exits of service areas;others are situated in the centre of the service areas.For the Cainiao Stations, 80% are located within 125 m of the exit;for the China Post stations, 80% are located within 175 m of the exit.4) The spatial distribution of the attended collection and delivery points in Changsha is unbalanced, with ‘more centre and fewer surrounding’.The centre is an ‘inverted triangle’, and the edge is an ‘orphan’, showing a northwest-southeast orientation and symmetrical along the axis.The layout of the attended collection and delivery points forms three core areas, and the number of sites decreases with the distance from the core.5) The number and distribution of the attended collection and delivery points are strongly consistent with the regional economic development level, population, and roadway system traffic convenience.Most attended collection and delivery points are on residential, scientific and educational, and commercial and financial land.
文摘By applying the technique of continuous partition of unity and Tychonoff's fixed point theorem,. some new collectively fixed point theorems for a family of set-valued, mappings defined on the product space of noncompact G-convex spaces are proved. As applications, some nonempty intersetion theorems of Ky Fan type for a family of subsets of the product space of G convex spaces are proved; An existence theorem of solutions for a system of nonlinear inequalities is given in G-convex spaces and some equilibrium existence of abstract economies are also obtained in G convex spaces. Our theorems theorems of improve, unify and generalized many important known results in recent literature.
基金Supported by the National Natural Science Foundation of China(10361005)
文摘Based on a KKM type theorem on FC-space, some new fixed point theorems for Fan-Browder type are established, and then some collectively fixed point theorems for a family of Ф-maps defined on product space of FC-spaces are given.These results generalize and improve many corresponding results.
文摘This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 innovation design was proposed.Second,field-coupling theoretical models of sunlight concentration,photoelectric conversion,and transmitting antennas were established,and a systematic optimization design method was proposed.Third,a beam waveform optimization methodology considering both a high beam collection efficiency and a circular stepped beam shape was proposed.Fourth,a control strategy was developed to control the condenser pointing toward the sun while maintaining the transmitting antenna toward the rectenna.Fifth,a high-efficiency heat radiator design method based on bionics and topology optimization was proposed.Sixth,a method for improving the rectenna array’s reception,rectification,and direct current(DC)power synthesis efficiencies is presented.Seventh,high-precision measurement technology for high-accuracy beam-pointing control was developed.Eighth,a smart mechanical structure was designed and developed.Finally,the developed SSPS ground demonstration and verification system has the capacity for sun tracking,a high concentration ratio,photoelectric conversion,microwave conversion and emission,microwave reception,and rectification,and thus satisfactory results were obtained.
文摘针对城市电网故障早期阶段的隐蔽性、潜伏性特点,通过构建“集体离群点-故障模式”的度量规则,对电网系统中全等级异常电流波动信号进行层次聚类分析,将区域性潜在故障检测问题转换为挖掘故障信号数据中的集体离群点问题。为提高检测效率,设计了一种基于不动点迭代法的层次聚类改进算法(Fixed point iteration based k-medoids,FPK-medoids),利用不动点较强的局部搜索能力提高聚类收敛速度。在测试数据集和实例数据集上进行实验,结果表明改进算法的收敛性能优于传统算法,检测模型能够精准识别电网中的区域性潜在故障。
文摘新能源汽车无人驾驶障碍检测过程中,受道路上的多种障碍物以及复杂的天气如雨雪、雾霾等影响,数据采集难度较大,导致驾驶障碍检测精度偏低。为此,提出车载激光雷达下新能源汽车无人驾驶障碍检测方法。采取水平安装的方式,将两个32线激光雷达以对称方式布置在无人驾驶汽车上,采集路面结构三维点云数据并用坐标转换同步数据;基于统计特征的离散点滤波算法,计算点云数据集的标准差和全局距离平均值,以此去除离散噪声点;采用基于密度的带有噪声的空间聚类(Density Based Spatial Clustering of Applications with Noise,DBSCAN)聚类算法实现新能源汽车无人驾驶的障碍检测。实验结果表明,所提方法抗噪能力较高,平均识别距离为82 m,障碍检测准确率均在92%以上,误检率最高为1.8%,且检测耗时仅为1.09 ms。
